Primary pulmonary tuberculosis in infancy: a resurgent disease in the urban United States

Radiological aspects in computed tomography as determinants in the diagnosis of pulmonary tuberculosis in immunocompetent infants

Objective

To describe the chest computed tomography (CT) findings in immunocompetent children under 36 months of age with pulmonary tuberculosis.

Materials and Methods

This was a descriptive case series conducted in the city of Rio de Janeiro, Brazil, between January 2004 and July 2013, involving 20 young children who underwent CT after undergoing chest X-rays that did not provide a definitive diagnosis.

Results

All of the participants had lymph node enlargement and consolidations. In 15 cases (75%), the consolidations were accompanied by atelectasis. Pulmonary cavitation was seen in 10 cases (50%), and cavitation within consolidations was seen in 7 (35%). The areas of cavitation and parenchymal destruction were not seen on conventional chest X-rays.

Conclusion

The radiological presentation of pulmonary tuberculosis in young children differs from that described in older children and adults. CT is an effective method for the early diagnosis of pulmonary tuberculosis in immunocompetent infants, allowing the rapid institution of specific treatment, which is crucial for halting disease progression, as well as for preventing local and systemic complications.

Aspectos tomográficos da consolidação lobar na tuberculose pulmonar primária

OBJETIVO: Descrever os aspectos tomográficos da tuberculose pulmonar primária manifestada inicialmente como consolidação lobar. MATERIAIS E MÉTODOS: O trabalho foi realizado no Hospital Municipal Jesus, Rio de Janeiro, RJ, no período de 2002 a 2006, avaliando-se retrospectivamente os aspectos tomográficos de quatro crianças de 3 a 14 meses de idade com tuberculose pulmonar primária manifestada inicialmente como consolidação lobar. RESULTADOS: O padrão radiológico mais frequente foi a consolidação lobar com calcificações, escavações e áreas de necrose de permeio, associada a abaulamento da cissura. Sinais de disseminação broncogênica e linfadenomegalia foram observados em todas elas. Consolidação de aspecto pseudotumoral, com efeito de massa, foi observada em um caso. CONCLUSÃO: Nos casos estudados observou-se que a tuberculose pulmonar primária manifestada como consolidação lobar apresenta imagens características à tomografia computadorizada, como escavações, áreas hipodensas e calcificações de permeio à consolidação. A associação com linfonodomegalias com centro necrótico e sinais de disseminação broncogênica reforçam o diagnóstico de tuberculose.

Airway involvement in pulmonary tuberculosis

Lymph gland involvement of the airways is common in young children with pulmonary tuberculosis. This lymph gland involvement leads to lymphobronchial tuberculosis, which presents with varying degrees of airway obstruction. These children are best assessed by fibreoptic bronchoscopy and are treated with the normal anti-tuberculosis regimens to which corticosteroids are added for a month and then weaned off over the next month. If, after a month, the children remain symptomatic, they must be re-evaluated by bronchoscopy and chest computed tomography. Surgery must be considered in children with severe airway obstruction still present at the time of the second evaluation. Surgical intervention consists of endoscopic or transthoracic enucleation of the lymph nodes. Only a small percentage of those with lymphobronchial tuberculosis will require surgery to relieve their airway obstruction.

Pulmonary tuberculosis in infants: radiographic and CT findings

OBJECTIVE

As complications of tuberculosis are frequent in infancy, correct diagnosis of tuberculosis in infants is important. The purposes of this study are to summarize radiographic and CT findings of pulmonary tuberculosis in infants and to determine the radiologic features frequently seen in infants with this disease.

CONCLUSION

Frequent radiologic findings of pulmonary tuberculosis in infants are mediastinal or hilar lymphadenopathy with central necrosis and air-space consolidations, especially masslike consolidations with low-attenuation areas or cavities within the consolidation. Disseminated pulmonary nodules and airway complications are also frequently detected in this age group. CT is a useful diagnostic technique in infants with tuberculosis because it can show parenchymal lesions and tuberculous lymphadenopathy better than chest radiography. CT scans can also be helpful when chest radiographs are inconclusive or complications of tuberculosis are suspected.

Specificity and sensitivity of chest radiographs in the diagnosis of paediatric pulmonary tuberculosis and the value of additional high-kilovolt radiographs

Tuberculosis (TB) remains the most common notifiable infectious disease in South Africa. The diagnosis of pulmonary TB in children is often very difficult because of the non-specific radiological signs and inter-observer variation in the interpretation of radiographs. The frontal high-kilovolt (kV) radiograph has been used to assess the effect of TB adenopathy on the tracheobronchial tree and to detect endobronchial lesions. The aims of the present study were to assess the specificity and sensitivity of chest radiographs in the diagnosis of pulmonary TB and to assess whether the addition of the high-kV radiograph affects these parameters. The study group consisted of paediatric patients suspected of having pulmonary TB over a 6-year period. These patients had clinical, bacteriological and radiographic examinations. Radiographs were examined by one experienced radiologist in two sittings separated by a 6-week interval. On the first sitting, only standard radiographs were examined and, on the second sitting, these were supplemented with high-kV radiographs. Differences in the detection of each recognized radiological feature of pulmonary TB before and after the addition of the high-kV film were analysed for statistical significance. The frequency of radiographic findings in our study compared favourably with other reports. No statistically significant differences for the detection of radiographic features consistent with pulmonary TB, or for the diagnosis of pulmonary TB, were demonstrated between the two sittings. Specificity increased from 74.4% to 86.6% with the addition of the high-kV view and sensitivity remained constant at 38.8%. The present study does not support the routine use of the frontal high-kV radiograph for the diagnosis of pulmonary TB. This paper also confirms the findings of others, that standard chest radiographs are a poor indicator of pulmonary TB in children.

Tuberculous pleural effusion: new pulmonary lesions during treatment

PURPOSE

To evaluate patients who have a paradoxical response (development of new opacities) to treatment for tuberculous pleural effusion not related to acquired immunodeficiency syndrome.

MATERIALS AND METHODS

In 16 patients, follow-up chest radiographs (n = 16) and initial (n = 2) and follow-up (n = 9) computed tomographic (CT) scans of the chest were retrospectively reviewed by two radiologists. Patient records (n = 16) and results of percutaneous needle aspiration and/or biopsy (n = 6) were reviewed by one radiologist.

RESULTS

Eighteen episodes of new lesion development were identified on radiographs in 16 patients. Each episode showed single (nine of 18 episodes, 50%) or multiple (nine of 18 episodes, 50%) nodules, most of which were in the peripheral lung (16 of 18 episodes, 89%) ipsilateral to the side of previous effusion (17 of 18 episodes, 94%). On CT scans, all lesions were peripheral pulmonary nodules, not round atelectasis. Needle aspiration and/or biopsy of the lesions showed findings consistent with tuberculosis in all six patients. Lesions usually evolved within 3 months after the start of medication (13 of 18 episodes) and finally disappeared (15 episodes) or left residual opacities (three episodes) 3-18 months later, with continuation of medication.

CONCLUSION

New lung lesions that develop during medication for tuberculous pleural effusion should be considered a transient worsening that ultimately improves with continuation of medication.

CT of pulmonary tuberculosis

CT scans in patients with primary tuberculosis commonly show lymphohematogenous spread of the disease, whereas those of postprimary (reactivation) tuberculosis commonly show bronchogenic spread. High-resolution CT (HCRT) is extremely helpful in understanding pathomorphological changes, mode of spread of the disease, and sequential morphological change after antituberculous chemotherapy, and possibly in diagnosing activity of the disease. Centrilobular 2- to 4-mm nodules or branching linear lesions representing intrabronchiolar and peribronchiolar caseation necrosis are the most common findings of early bronchogenic spread of tuberculosis. The 2- to 4-mm centrilobular nodules may coalesce to form 5- to 8-mm nodules or lobular consolidation. Cavitation usually begins at the central portion of a lobule around the bronchioles. Resolution of the tuberculous lesions occurs with antituberculous chemotherapy, resulting in varying degrees of fibrosis, bronchovascular distortion, emphysema, and bronchiectasis. HRCT may show both paracicatricial irregular emphysema and lobular emphysema. CT findings of early miliary dissemination commonly include ground-glass opacification with barely discernible nodules that show discrete miliary nodules thereafter. CT also is useful in the evaluation of long-standing destructive pulmonary lesions and tracheobronchial tuberculosis.

Pulmonary tuberculosis in children

TB is no longer the scourge it once was, but it remains an important cause of morbidity and mortality worldwide. Fueled by increasing poverty, homelessness, immigration, drug abuse, declining prevention programs, and the HIV epidemic, its incidence in the United States has increased dramatically. The complex natural history of pulmonary TB in children is reflected in its varied radiographic manifestations. Strict distinction between "adult" and "childhood" patterns of TB should be avoided (Fig 16). In general, adenopathy is the footprint of childhood primary pulmonary TB, with or without a readily apparent primary parenchymal focus or pleural effusion. Infants and young children are more likely to present with adenopathy only than their older counterparts. The pediatric tracheobronchial tree is particularly susceptible to compression by surrounding nodes, producing segmental atelectasis, or less commonly, obstructive emphysema. Self-limited lymphohematogenous dissemination is the rule, but actual miliary disease is the exception. Pediatric postprimary TB, when it occurs, is usually observed in adolescents. It is characterized by parenchymal disease with an anatomic bias for the upper lung zones. Proper image interpretation is inextricably dependent on an understanding of the pathogenesis of this fascinating and often baffling illness whose appearance widely varies depending on host age and immunity as well as the virulence of the organism itself.

Proposal of an improved score method for the diagnosis of pulmonary tuberculosis in childhood in developing countries

210 children aged less than 5 years, referred to the Arua Regional TB Centre (Uganda) for suspected pulmonary tuberculosis (PTB), were examined by anamnesis, clinical examination, Mantoux test, gastric washing, chest X-ray. The response to treatment criterion was applied to the patients treated. According to the score method suggested by Ghidey and Habte, 31 children were diagnosed as PTB patients. 30 of the 31 children with PTB tested positive for alcohol acid-fast bacilli (AAFB) in the aspirated juice. The Mantoux test and X-rays gave a minor contribution to diagnosis. The clinical results are commented. A statistical analysis was carried out to evaluate the role of gastric washing in the diagnosis of PTB in children under 5 years of age (sensitivity, 96.8%; specificity, 92.2%; positive predictive value, 68.2%; negative predictive value, 99.4%). The response to treatment was also evaluated. A modified enlarged score method (based on gastric washing and including response to treatment) is proposed to be applied in developing countries where chest X-ray and other facilities are often lacking.